How to maintain CNC equipment?

 
The correct operation and maintenance of numerical control equipment is one of the key factors for the correct use of numerical control equipment. Correct operation and use can prevent abnormal wear of machine tools, avoid sudden failure; Good daily maintenance can keep the equipment in good technical condition, delay the deterioration process, timely find and eliminate hidden trouble, so as to ensure safe operation.
First, the use of CNC equipment environment
In order to improve the service life of CNC equipment, the general requirements to avoid direct sunlight and other thermal radiation, to avoid too wet, too much dust or corrosive gas places. Precision CNC equipment should be kept away from large vibration equipment, such as punch, forging equipment, etc.
Two, good power supply guarantee
In order to avoid the large fluctuation of power supply (greater than ±10%) and the influence of the possible instantaneous interference signal, NUMERICAL control equipment generally adopts special line power supply (such as from the low-voltage distribution room for a separate numerical control machine tool) or additional voltage regulator, etc., can reduce the influence of power supply quality and electrical interference.
3. Formulate effective operating procedures
In the use and management of CNC machine tools, a series of practical and effective operating procedures should be formulated. For example, lubrication, maintenance, reasonable use and standard shift system, is the main content of the use and management of CNC equipment. Making and obeying the operation rules is one of the important measures to ensure the safe operation of CNC machine tools. Practice has proved that many failures can be reduced by following the operating procedures.
Four, NUMERICAL control equipment should not be sealed up for a long time
After the purchase of CNC machine tools to make full use of, especially put into use in the first year, so that its vulnerable to failure as soon as possible exposed, to be eliminated in the warranty period. Processing, as far as possible to reduce the opening and closing of CNC machine tool spindle, in order to reduce the wear of clutch, gear and other components. No processing task, nc machine tools are regularly electricity, or electricity 1 ~ 2 times a week, every time an empty running 1 hour or so, to take advantage of the machine tool itself calorific value to reduce the humidity inside the machine, make the electronic components shall not be affected with damp be affected with damp, at the same time can also be found in a timely manner for battery power shortage alarm, to prevent the loss of the system setting parameter.
Five, maintenance of CNC machine tools
There are many kinds of CNC machine tools, all kinds of CNC machine tools because of their different functions, structures and systems, each with different characteristics. The maintenance of the content and rules also have their own characteristics, specific should be based on the type of machine tool, model and actual use of the situation, and reference to the machine tool manual requirements, formulate and establish the necessary regular, grading maintenance system. Here are some common and general maintenance tips.
(a) maintenance of numerical control system
1. Strictly abide by the operating procedures and daily maintenance system
Numerical control equipment operators to strictly abide by the operation rules and daily maintenance system, the quality of the operator's technical service is an important factor affecting the frequency of failure. When the machine fails, the operator should pay attention to the retention of the site, and to the maintenance personnel to truthfully explain the situation before and after the failure, in order to facilitate the analysis, diagnosis of the cause of the failure, timely elimination.
2. Prevent dust and dirt from entering the nc device
There are generally oil mist, dust and even metal powder in the air of the machining workshop. Once they fall on the circuit board or electronic devices in the NUMERICAL control system, it is easy to cause the insulation resistance between components to decline, and even lead to the damage of components and circuit boards. Some users in summer in order to make numerical control system can overload long-term work, take to open the door of numerical control cabinet to heat, this is a very undesirable method, its will eventually lead to numerical control system to accelerate damage, should reduce to open numerical control cabinet and strong electric cabinet door.
3. Prevent the system from overheating
Each cooling fan on the CNC cabinet should be checked for normal operation. Check whether the air duct filter is blocked every six months or every quarter. If the dust on the filter net accumulates too much and is not cleaned in time, the temperature in the CNC cabinet will be too high.
4. Regular maintenance of input/output devices of CNC system
CNC machine tools produced before the 1980s, mostly with photoelectric tape readers, if the tape reading part is contaminated, will lead to errors in reading information. To this end, the photoelectric reading machine must be maintained according to the provisions.
5, dc motor brush regular inspection and replacement
Excessive wear of dc motor brush will affect the performance of the motor, and even cause damage to the motor. Therefore, the motor brush should be checked and replaced regularly. CNC lathes, CNC milling machines, machining centers, etc., should be inspected once a year.
6. Check and replace storage batteries regularly
The general CNC system is provided with rechargeable battery maintenance circuit for CMOSRAM storage devices to ensure that the system can maintain the contents of its memory during the period of no power. Under normal circumstances, even if it has not failed, it should be replaced once a year to ensure the normal operation of the system. Battery replacement should be carried out under the power supply of the CNC system to prevent the loss of information in the RAM during replacement.
7. Maintenance of spare circuit board
When the spare printed circuit board is not used for a long time, it should be installed regularly in the NUMERICAL control system for a period of time to prevent damage.
(2) Maintenance of mechanical components
1. Maintenance of main transmission chain
Adjust the tightness of the driving belt of the main shaft regularly to prevent the phenomenon of losing rotation caused by the slip of the belt; Check the constant temperature oil tank of spindle lubrication, adjust the temperature range, replenish the oil amount in time, and clean the filter; After the tool clamping device in the spindle is used for a long time, there will be a gap, which will affect the clamping of the tool. It is necessary to adjust the displacement of the hydraulic cylinder piston in time.
2. Maintenance of ball screw thread pair
Check and adjust the axial clearance of the screw thread pair regularly to ensure the reverse transmission accuracy and axial stiffness; Regularly check whether the connection between the lead screw and the bed is loose; If the protective device of the lead screw is damaged, it should be replaced in time to prevent dust or chips from entering.
3. Maintenance of knife library and knife changing manipulator
It is strictly prohibited to load the overweight and long tool into the knife library, in order to avoid the collision of the tool or the tool and the workpiece and fixture when the manipulator changes the tool; Regularly check whether the zero return position of the tool library is correct, check whether the position of the tool return point of the spindle of the machine tool is in place, and adjust it in time; Boot, should make the knife library and manipulator empty operation, check whether all parts of the work is normal, especially the travel switch and solenoid valve can normal action; Check whether the tool is reliably locked on the manipulator. If abnormal, it should be dealt with in time.
(3) Maintenance of hydraulic and pneumatic systems
Regularly clean or replace the filters or filter screens of lubrication, hydraulic and pneumatic systems; Carry out oil quality test and inspection on the hydraulic system regularly, add and replace hydraulic oil; Regularly drain water from the air pressure system water filter.
(4) Maintenance of machine tool accuracy
Check and calibrate machine level and mechanical accuracy regularly. There are two kinds of correction methods for mechanical accuracy: hard and soft. The soft method is mainly through system parameter compensation, such as screw reverse clearance compensation, fixed point compensation of coordinate positioning accuracy, machine tool reference point position correction, etc. The hard method is generally carried out when the machine tool is overhauled, such as repairing and scraping the guide rail and adjusting the reverse clearance of the ball screw nut pair.